1. Field of the Invention
This invention relates to the field of fluid dispensers and specifically to an improved dispensing device for containing multiple fluids in non-vented containers, mixing them and dispensing the mixture to stained textile fabrics, especially carpet.
2. Description of the Prior Art
Stains are a major reason why homeowners replace their carpet. Misinformation abounds regarding spot cleaning carpet, even though the rules remain the same: prompt treatment with the correct chemicals and procedures. Many a spot has become a permanent stain from neglect, and/or improper treatments and procedures. Store shelves overflow with spot cleaners that don't work; many of which if applied to carpeting, will void the Carpet Warranty.
Although many common stains from soils and oils can be removed with a simple mist & blot procedure, using dilute liquid hand dishwashing detergent solution, similar treatments are ineffective in removing organic dye type stains from coffee, tea, urine, wine, and artificial dyes like Red FD&C 40. Homeowners buy powdered “oxygen cleaners” and mix them with water then apply the solution to their dye type stains. These oxidation agents are only marginally effective on organic dyes, and only if they're applied with patience and persistence. The reactions are slow and short-lived. Novice spotters get impatient and mix too much powder relative to water. They reason, “if a little is good, a lot is better.” Manufactures contribute to the problem by encouraging homeowners to “pour” the solution. Pouring any liquid onto a carpet is bad procedure, especially in the case of overly concentrated oxidizing agents. Pouring can cause permanent damage to fibers, backing, padding and underlying wooden sub floors. There is no reason for any of this damage. Professional carpet cleaners use more effective chemicals and procedures for treating dye type stains.
Professional cleaners prefer to use a mixture of Hydrogen peroxide plus an alkaline solution for treating organic dye type stains. The mixture, herein referred to as ‘two-part oxidant’ creates a short-lived reaction that goes to completion in about 30 minutes, so the two liquids must be kept separate until the time of use. Chemical manufacturers sell professional cleaners these and other two-part oxidant products to be mixed on the cleaning job. The two-part oxidant typically comes in sealed, paired pint containers with part A being hydrogen peroxide and part B being an ammonia or amine/surfactant solution. The procedure involves mixing roughly equal amounts of parts A & B in a measuring cup then inserting the dip tube of a trigger sprayer into the mixture and misting the stain. Several of these ‘mix and mist’ applications may be required to remove the dye type stains. It's guesswork estimating how much of the mixture will be needed for a given job. If the user mixes too much, it's wasted. If he doesn't mix enough, he must stop and measure more. And if the user accidentally leaves the cap to the hydrogen peroxide container slightly ajar, the hydrogen peroxide goes flat rendering the mixture ineffective. There has as yet been devised a means of extending the shelf-life of the unstable chemicals like hydrogen peroxide. Manufactures only sell their two-part products in the smaller sized containers. They know that larger containers would accumulate too much air over the unstable chemicals as they emptied which would allow them to go flat too fast. So pros go through a lot of these smaller pint sized bottles in their work. Once they are empty, they are discarded. Professional cleaners need a more efficient means of storing, mixing, and dispensing their two-part oxidizing agents.
Other specialty products are available to professionals for treating the more difficult to remove artificial dyes like Red FD&C 40. Some are two-part products which are mixed 50:50, misted onto the spot, then accelerated with the known heat transfer process. Others incorporate the known heat transfer process. Beck and Harris, U.S. Pat. No. 5,002,684 (1991) describes the use of ‘moist heat’ used in connection with his patented dye removal composition and method. But neglect and/or improper treatment can permanently set dye related stains such that even these specialty products are ineffective in removing these dye stains. As Beck and Harris state, “ . . . more carpets are replaced because of stains which cannot be removed than from carpets being worn out.”
Homeowners sometimes have an advantage over the pros; they are there when the spill occurs. If they just had the right chemicals and acted promptly with them, they would be successful in removing most of their dye related stains. Two-part oxidant products would remove their organic dye type stains and the specialty two-part products would help them with the artificial dyes so the heat transfer process would probably not even be necessary. But unfortunately, these two-part products are not available off-the-shelf. Regarding the two-part oxidant, homeowners would experience the same problems the pros have; they would discover their hydrogen peroxide had gone flat before it had been used up. They won't need it often but when they do, it won't perform.
Applicant has made an effort to utilize existing aerosol technology in providing a device to solve these dispensing problems. However, aerosolizing manufacturers are reluctant to develop an aerosol system that contains two-part oxidants in a single container because of the corrosive effect of the mixture on internal metal components. Even the bag & can system would expose the corrosive mixture to the internal metal actuator. Plus, such a design would be expensive to develop. Actually, there is no need for this expense since there are several trigger sprayer type multi-compartment dispensing devices that are capable of containing, mixing and dispensing two-part oxidants.
Various multi-compartment dispensing devices are known in the art which keep liquids separate until the time of mixing. Notable of these designs is U.S. Pat. No. 4,355,739, to Vierkotter (1982). For general purpose cleaners, this device would probably work fine. However, popular solvents like D-limonene might damage its specialized components. U.S. Pat. No. 4,826,048 to Skorka, et al. (1989) is another of these complex designs, featuring a bridge-like top cap with unique multiple piston-type discharge pumps. It would likely be costly to repair. This invention clearly demonstrates another problem with all rigid neck type dispensers: it is awkward to dispense fluids onto a horizontal surface. U.S. Pat. No. 5,152,461 to Proctor (1992) is another specialized and elaborate multi-compartment device. It retails for several times that of a conventional trigger sprayer ($30 on the Amway website). If one of its valves or many moving parts were to fail, the entire device would likely have to be replaced.
U.S. Pat. No. 5,472,119 to Park et al. (1995), teaches an ingenious multi-compartment dispenser that simultaneously vents and dispenses two fluids. They teach that “fluid drawn . . . must be replaced by air (venting) for pumping to continue else containers simply collapse.” So, theirs replaces the fluid with fresh air every time the trigger is actuated (squeezed). But this venting is not a preferable way to contain unstable chemicals like hydrogen peroxide. Venting is like leaving the cap off the bottle. A closely related subsequent U.S. Pat. No. 5,492,540 to Leifheit, et al. (1996) addresses mixing incompatible chemicals. Leifheit, et al. correctly claim hydrogen peroxide to be a superior stain fighter yet they not only fail to address the problem caused by venting, but they are also silent on providing a means of solving the problem of gaseous pressure build-up inside the mixing chamber. U.S. Pat. No. 5,767,055 to Choy (1998) defines and offers solutions to the unexpected ‘shooting’ problem of earlier dispensers by means of minimizing the size of the mixing chamber or moving it beyond the nozzle. Yet, Choy's device suffers from some of the same problems as those previously mentioned, namely it uses specialized manufacturing which makes it expensive and hard to maintain, and the rigid neck which makes it awkward to mist onto horizontal surfaces. Choy mentions H2O2 as a suitable oxidizing agent yet even he is silent on sustaining its potency.
Anybody who has ever had their soda pop go ‘flat’ would appreciate a means of sustaining an unstable chemical's potency. There are inventive repressurizing devises available that prevent soda pop from going flat. U.S. Pat. No. 4,723,670 to Robinson (1988) discloses a device that “pressurizes a beverage container with ambient air” so the gas is forced to stay in solution. Some two part products don't require the use of unstable chemicals but in the case of the two part oxidant product, hydrogen peroxide is the oxidant of choice. Both the professional cleaner and the homeowner alike could benefit from a means of maintaining its potency so when a spill occurs, their two part oxidant mixture is effective.